Radiation therapy has been employed to treat tumorous tissue. In radiation therapy, a high energy beam is applied from an external radiation source towards the patient. The external radiation source, which may be rotating (as in the case for arc therapy), produces a beam of radiation that is directed into the patient to the target site. The dose and placement of the dose must be accurately controlled to ensure that the tumor receives sufficient radiation, and that damage to the surrounding healthy tissue is minimized.
In certain treatment procedures, such as a procedure for treating a brain tumor, it may be desirable to produce a treatment radiation beam having a small profile (e.g., cross sectional dimension), thereby allowing precise treatment of the targeted tissue. In such treatment procedure, a conical collimator may be employed to change a cone beam provided by the radiation source into a pencil beam with a certain desired cross sectional dimension. The pencil beam allows targeted tissue to be precisely irradiated. In some cases, different conical collimators with different configurations may be provided for producing pencil beams with different respective cross sectional dimensions. During use, the operator of the radiation machine chooses one of the available conical collimators for use with the radiation machine, depending on the particular size of the pencil beam required by a treatment plan.
In existing techniques, the operator may be required to manually check the conical collimator to make sure that the particular conical collimator being used with the radiation machine is the proper size. However, Applicants of the subject application determines that manually checking the conical collimator is inconvenient and may not be reliable as such technique may be subject to human error. Thus, applicants of the subject application determine that it would be desirable to provide a new device and method for conical collimator verification.